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<script>
	//&&
	console.log('建哥很帅' && true);//
	console.log(true && false); //false
	console.log(false && false); //false
	console.log(!true); //false;
	console.log(!!true);//ture
	console.log(!!!true);//false
	//奇数为它自身对立面，偶数就是自身
</script>